Got my new Samsung QLED this morning.. the remote is a challenge.
i managed to open it by: place the remote back side up on top of a towel, then using a flat-head screw driver, push on the back of the arrow in the direction of the arrow, it popped right open.
"try using a rubber glove and pushing against the arrow...with traction, it opens easily! "
BINGO. I used some latex surgeons gloves (unpowedered) that we had. (My wife's a medical technologist.) The extra traction got the back cover off. Found one battery corroded. Don't know why; we use the remote constantly.